Bone physiology in dogs is very different than humans, so the typical osteoporotic concerns that humans have are generally very rare in canines. Nonetheless, there are certain bone conditions that can affect dogs. These can be hereditary or breed-related (genetic deformities), cancer-related (osteosarcoma), or caused by other factors. Skeletal (bone and joint) disorders are divided into two major categories: developmental and degenerative problems. Developmental problems (such as hip dysplasia) arise where the joint does not develops incorrectly. Degenerative problems (such as osteoarthritis), on the other hand, are caused over time through wear and tear and stress on the bones and joints. The following are a few of the commonly found bone diseases and conditions found in dogs:

Osteomyelitis is inflammation of the bone, usually caused by a bacterial infection. It is often seen in dogs following a traumatic bone injury (where there is an open wound), post-operatively after orthopedic procedures (such as bone fracture repair or TPLO). This condition can delay or prevent union of the bone, and is usually treated with antibiotics and anti-inflammatory medications.

Can be both benign and malignant. The most common bone tumor is osteosarcoma of the radius, humerus, femur, or tibia.Osteosarcoma is a rapidly growing and destructive cancer of the bone. This condition is more commonly seen in senior, large breed dogs. In the case of osteosarcoma, early detection is key to the survival of the dog, as treatment can involve extensive chemotherapy and surgery. Also, Dogs that are between 7-10 years generally have a better chance of survival than younger and older dogs.

Are sometimes seen in dogs when they are not fed the right diet for their breed/weight/or age. The bone is a dynamic structure that constantly remodels and is replaced several times in a dogs lifetime. Ensuring that a dog has the proper nutrition required for strong bones is important to ensuring that the dog stays healthy. Reduced bone mass, bone deformities, bony growths, fractures, and loose teeth are all conditions that can result from nutritional deficiencies.

This content is written by our Clinical Advisory Board for informational purposes only. It should not be viewed as an endorsement for any product or as a substitute for the advice of your veterinarian.

Degenerative Joint Disease (DJD) is an overarching term used to describe a number of chronic and progressive joint conditions (including osteoarthritis and and hip dysplasia). Characteristic of these conditions are where cartilage between the bones becomes worn away, causing the bones to painfully rub together at the joint. Additionally small bony growths (osteophytes) may develop in the joint in an attempt to try and stabilize the joint. Cartilage is damaged by abnormal mechanical stresses (congenital deformities, abnormal conformation or trauma) or may be idiopathic (no identifiable cause). One or several joints may be affected.

Dog limping is one of the most common symptoms that indicate a potential joint disorder in dogs, but can be actually be caused by a number of reasons. The video below provides an overview of some of the most common causes of dog limping.

Signs of DJD in dogs include limping, stiffness, clicking sounds at the joints, and a hesitancy to run, jump or climb stairs. Signs may worsen after overexertion or in cold and damp weather. Function is lost over time due to fibrosis and pain which ends with exercise intolerance, constant lameness, decreased range of motion and muscle wasting.

Arthritis in dogs is a DJD condition that is more commonly seen in older pets from years of wear and tear on the joints. This condition can affect any joint in the body such as the shoulder, elbow, knee, hip, and back. One in five dogs suffers from some form of arthritis, though it is estimated that only 50 percent of those suffering from the condition receive treatment. Obesity plays a critical role by putting added pressure on the joints and genetic factors also must be considered since some breeds are more prone to joint pain issues than others. Newfoundlands have the highest prevalence of cruciate ligament disease of all breeds. Rottweilers have more knee and ankle problems.

Hip Dysplasia in Dogs is often referred to as CHD or just HD, is an inherited (developmental) disorder of hip joint malformation, where the ball-shaped end of the thigh bone (femur) fails to fit snugly in the socket-shape of the pelvic bone. If the ligaments around the socket are loose, the head of the femur will start to slip from the socket. This causes gradual hind-end lameness and pain.The following breeds are particularly susceptible to this form of hip pain: German shepherds, Golden retrievers, Great danes, Labrador retrievers, Rottweilers, and Saint bernards.

A dog suffering from hip dysplasia might have the condition from as early as five months yet not exhibit any symptoms until well into adulthood. The CHD symptoms include: limp, abnormal gait, hopping when running, clicking sound when walking, pain in rear legs, loss of muscle mass in thigh, low energy, reluctance to climb stairs or jump up on bed, and abnormally wide hips.

Treatment for canine hip dysplasia varies depending on the age of the dog, the severity of the condition, and the options available to dog and owner. Among medical options weight control is critical. Any excess weight will only aggravate the condition. If surgery is not an option in addition to losing any excess weight, pain medications and supplements are used to control the dog’s pain. In more severe cases, your veterinarian might suggest surgical options ranging from triple pelvic osteotomy (TPO), pubic symphodesis, femoral head ostectomy (FHO), and hip replacement.

Is a condition in which the kneecap (patella) has slipped out, or dislocated, from the smooth groove in which it normally rides up and down. It has slipped medially, which is to say towards the opposite leg, as opposed to laterally, which would be away from the dog entirely. With the patella dislocated (or luxated) medially, the knee cannot extend properly and stays bent and can cause lameness. Smaller breeds, especially Miniature and Toy Poodles, have the highest incidence of patella luxation. Approximately 50% of affected dogs have both knees involved while the other 50% has only one knee involved.

This content is written by our Clinical Advisory Board for informational purposes only. It should not be viewed as an endorsement for any product or as a substitute for the advice of your veterinarian.

Broken bones in dogs are pretty common. Before discussing symptoms, let’s first discuss what bones are and their composition. The bone is living, growing biomaterial that has a multitude of functions, from providing a skeletal framework to storing minerals. Bone is mostly composed of collagen, calcium and other minerals. Collagen is a protein that provides a soft framework. Calcium is a mineral that adds strength and hardens the framework. This combination of collagen and calcium makes bone strong and flexible. To learn more about the anatomy of the bones, visit our section on the canine skeletal system.

Broken bones in dogs are typically caused from accidents, such as getting hit by a car, falling, and repetitive activity. In dogs, femur fractures make up 45% of the fracture cases (a majority of these involve the hind legs). The second most common long bone fracture in dogs is the tibia, followed by the radius and ulna. It is common for dogs to fracture both the radius and ulna in traumatic accidents such as car accidents or falls. Humeral fractures account for 10% of all limb fractures.

Some people mistakenly believe that a fracture and a break are different in their severity or type - this is not true. Anytime a bone breaks, it is called a fracture. There are, however, different TYPES of broken bones (i.e. fractures) in dogs.

When an unusual or atypical amount of physical stress is exerted onto the bone of a dog, it can result in a break or fracture. Some common causes include:

• Jumping from a Height - dogs can injure themselves when they jump from furniture (such as a couch or tall bed). Just like with humans, your dog’s size and physical strength will determine whether this is something you should be concerned about. For example, a 90 lb Labrador may be able to regularly jump off a bed or sofa without injury. Meanwhile, a 4 lb teacup Chihuahua or Maltese could very well suffer a broken leg from such a fall.
• Pre-existing Injury – Dogs that have broken a leg before can often re-injure or hurt themselves in the same spot. Even normal activities can cause problems if the dog’s is not properly set or strengthened after the initial injury. Make sure to speak with your veterinarian about preventive steps you can take to ensure that you are providing proper bone and joint support for your dog in such cases.
• Landing on Hard Surfaces - When a jump from a height is combined with a hard surface, such as concrete or wood flooring, the impact can cause fracture.
• Getting Hit By a Car - Dogs that get out of the fenced yard can get seriously injured by the impact of a car. In some cases, these injuries can result in death. Neo, the rescue dog who inspired Boneo Canine, suffered from a compound fracture after getting hit by a car. Learn more about Neo here.
• Retractable Leashes - Retractable leashes may seem like a convenient way to give your dog freedom, but think twice. These leashes can be extremely dangerous for your dog, you, and anyone around you, if you have a rowdy or uncontrollable dog. Retractable leashes have the potential of wrapping around limbs and causing serious leg injuries.
• Rough-housing - If you have multiple dogs or take your dog to the dog park, they often can get outsized by other dogs. Even innocent rough-play can result in injury and fracture.
• Surgery – Certain orthopedic surgeries, such as a TPLO surgery, require the bone to be cut and reshaped. Even though a bone leveling or cutting procedure is supervised by a veterinarian, it is still considered a broken bone for healing purposes.

Based on the complications associated, fractures are classified as simple, compound or complicated.

• Simple fractures involve only the bone, with little damage to the surrounding tissue. This type of broken bone is relatively simple to fix with a cast, crate, supplement, and restricted activity.
• Compound fractures occur when a bone breaks and fragments penetrate the skin. This fracture is more difficult to fix due to the involvement of damaged soft tissue surrounding the fractured bone. Compound fractures usually require clean up of the fragments and a plate to ensure union.
• Complicated fractures are the most serious type of broken bone. They are severe breaks accompanied by an additional problem, such as a pinched or torn nerve, a punctured vein or artery, or a pierced body cavity or joint.

When dogs are in pain, they will often start whimpering, howling and exhibit visual signs of pain. Be observant for signs of swelling, an inability to put any kind of weight on the affected limb (dogs will often "carry" a broken limb rather than walk on it), inability or unwillingness to climb or jump down, and limping.

Also watch for behavior changes in your dog. When dogs are not feeling well, they don't usually act "normal". Growling or showing teeth when you touch the affected area is common, as dogs can get scared when something is wrong with their bodies. It's also very common to experience loss of appetite and start hiding.

Want to learn more about dog fractures? Watch the video below:

This content is written by our Clinical Advisory Board for informational purposes only. It should not be viewed as an endorsement for any product or as a substitute for the advice of your veterinarian.

When a dog has a fracture, the bone begins to undergo a healing process. Fracture healing in dogs can take several weeks to months and is dependent on several factors, such as the age of the dog and severity of the fracture. But what exactly is the process of how the bone is repaired?

After a dog suffers from a broken bone, there are four distinct stages of fracture healing (as seen in the video below). These include the Inflammatory Phases 1 and 2, the Repair Phase, and the Remodeling Phase. Collectively, this process is called BONE REMODELING.

For a simpler explanation of this process, make sure to watch the video below.

Within hours of a fracture, the damaged area of the bone becomes inflamed. Blood flows to the fracture site, which causes redness and heat. A blood clot called a hematoma develops around the fracture site. The purpose of this blood clot is to prevent further bleeding and blood loss. Blood clotting also sets the stage to start the process of repair.

In the second part of the inflammatory phase, the immune cells take center stage as the hematoma begins to convert into a connective tissue called granulation tissue. The purpose of granulation tissue is to provide a capsule for immune cells and growth factors to enter. These specialized cells will stimulate the development of new blood vessels and bone formation in later phases. The initial inflammatory phases lasts for 3-4 days and potentially longer, depending on the degree of fracture. Once these phases have taken place, the broken bone can now begin to form a callus.

After the reactive stage, the granulation tissue on the fracture site is ready to move into callus formation. The purpose of the repair phase is to provide a temporary splint to join broken ends together. Callus formation has two parts - Soft Callus Formation and Hard Callus Formation.

• Soft Callus Formation – Soft callus (made mostly of collagen) is created around the fracture by a group of cells called chondroblasts. During this time, there are also specialized bone cells in a dog’s body that are working called osteoblasts and osteoclasts. Osteoclasts break down bone - they eat away at the old bone, creating a cavity. Osteoblasts are bone-forming cells. They secrete osteoid, an unmineralized organic matrix.
• Hard Callus Formation – In the second stage of the repair phase, the soft callus is mineralized by osteoblasts into a hard callus, called woven bone. Hard callus bridges the new bone to existing bone.

During fracture healing, progression from soft to hard callus depends upon an adequate blood supply and a gradual increase in stability at the fracture site. The balanced action of osteoclastic resorption and osteoblastic deposition is promoted by bio-replenishments (i.e. lactoferrin and R-ELF), bone vitamins and minerals.

At the end of the repair phase, bone union is achieved, but the structure of the fracture site differs from that of the original bone. This type of bone is called woven bone; it is comprised of a randomized organization of collagen fibers and is mechanically weak. It is important to keep your dog immobilized as much as possible because hard callus lacks the strength and rigidity of the original bone. Note - the injured bone will have regained enough strength and rigidity to allow low impact exercise.

Fracture healing is completed during the remodeling stage in which the healing bone (if set properly through a splint, cast, or other structural support) is restored to its original shape, structure, and mechanical strength. During this final phase, the large callus is reduced to the size of actual bone at the fracture site. The woven/primary bone is replaced with secondary lamellar bone. This final mineralization process can take weeks, months, or even up to a year.

The time required to achieve complete union and mineralization varies based on the severity and location of the fracture. The status of the adjacent soft tissues and patient characteristics such as breed, age, health status, concurrent injuries/diseases also influence the rate of healing.

• Puppies – Broken bone healing time in puppies is relatively short - about 2 to 4 weeks. Younger dogs have more bone building cells (osteoblasts) because they are growing, so their bones are constantly remodeling anyway. This time frame can of course differ based on the severity of the fracture and condition.
• Adult Dogs – For adult and senior dogs, broken bone healing time is usually between 6 to 12 weeks. This length of time can be more depending on the nature of the fracture. The chart below shows some of the average healing times associated with fractures in dogs.

Just as there are many factors that can influence your dog's bone healing, there are also many factors that can delay bone healing that should be taken into consideration, such as:

• Age – An older dog takes longer to heal (about 12 weeks or more) where as a growing puppy may heal in as little as 5 weeks.
• Lack of Exercise Prior to Injury – Moderate exercise helps maintain muscle mass and preserve joint flexibility.
• Obesity – Weight can place stress and strain on the bones and joints. This can cause a delay in the ability of the fracture to heal.
• Poor Nutrition – New bones require mineralization. If a dog is lacking in a nutritious diet he or she may miss out on vital nutrients that promote bone remodeling.
• Severity – The severity of the fracture affects the formation of blood clotting around the fracture site and can delay the formation of repair tissue.
• Pre-existing Conditions – Joint disorders, cartilage deterioration, nutrient deficiencies, previous surgeries, even genetic pre-disposition can delay or affect the rate of healing.
• Infection – Whenever the bone is exposed there is always the risk of bacterial contamination and infection. This can delay union. Antibiotics can help to combat infection, but many bacteria are resistant and can still thrive.
• Excessive Movement – Movement at the fracture site causes a delay in healing due to a non-union of the bone ends.
• Delayed Visit to Your Vet – Your vet can check to make sure your dog doesn't have any infections. They can review x-rays to make sure the broken bone is healing properly. Your vet can also perform surgery to remove any broken fragments and apply a proper cast.

This content is written by our Clinical Advisory Board for informational purposes only. It should not be viewed as an endorsement for any product or as a substitute for the advice of your veterinarian.